Screening devices of this type are sufficiently known from the state of the art and are utilized, for example, for removing coarse screenings (wood, stones, etc.) from wastewater flowing in a sewer. Good separation efficiency and, therefore, the efficiency of the screening device are dependent, in this case, in particular, on the flow conditions of the sewer and the geometry of the screening device.
The sieve grates of known screening devices extend transversely to the flow direction of the wastewater reaching the screening device. Incoming wastewater therefore flows against the sieve grate from the front, wherein the wastewater passes through the sieve grate without greater deflections, i.e., the wastewater essentially retains its flow direction.
Various solutions for achieving a high separation efficiency already exist from the state of the art. For example, the separation efficiency can be increased by reducing the spacing of the grating bars of the sieve grate. It is disadvantageous, however, that the throughput capacity and, therefore, the efficiency of the screening device decrease as a result.
Moreover, the known screening devices have the disadvantage that their screen surface is limited by the cross section of the sewer.